An Inventory of Problems-29 (IOP-29) study investigating feigned schizophrenia and random responding in a British community sample.

Compared to other Western countries, malingering research is still relatively scarce in the United Kingdom, partly because only a few brief and easy-to-use symptom validity tests (SVTs) have been validated for use with British test-takers. This online study examined the validity of the Inventory of Problems-29 (IOP-29) in detecting feigned schizophrenia and random responding in 151 British volunteers. Each participant took three IOP-29 test administrations: (a) responding honestly; (b) pretending to suffer from schizophrenia; and (c) responding at random. Additionally, they also responded to a schizotypy measure (O-LIFE) under standard instruction. The IOP-29's feigning scale (FDS) showed excellent validity in discriminating honest responding from feigned schizophrenia (AUC = .99), and its classification accuracy was not significantly affected by the presence of schizotypal traits. Additionally, a recently introduced IOP-29 scale aimed at detecting random responding (RRS) demonstrated very promising results.

A dimensional measure of schizotypy: cross-cultural adaptation and validation of the Oxford-Liverpool Inventory of Feelings and Experiences short version for Brazilian Portuguese (O-LIFE-S)

Abstract Introduction The Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE) is a widely-used scale, and the first to include a dimensional approach to understanding schizotypy. Objective To adapt the short version of the O-LIFE (O-LIFE-S) into Brazilian Portuguese. Method a) Two independent bilingual professionals translated the original instrument into Brazilian Portuguese; b) a third bilingual professional summarized the two translations; c) a fourth bilingual expert translated the Portuguese version back into English; d) this back-translation was adjusted by a committee of psychology experts; e) a pilot study was conducted with 10 participants from the general population. Results O-LIFE-S was considered ready to be used in a formal validation study in Brazil. Conclusion The scale appears to cover the dimensional approach to schizotypy. However, a future validation study needs to be conducted to determine the internal consistency and reliability of the Brazilian Portuguese version of the O-LIFE-S .

Chronic pain after groin hernia repair: pain characteristics and impact on quality of life.

BACKGROUND: Chronic postsurgical pain (CPSP) after hernia repair research has mainly relied on unconfirmed self-reporting. We aimed to describe confirmed CPSP incidence, management, and quality of life (QoL) in a 2-year prospective study. METHODS: Multicenter study (GENDOLCAT) of 3890 patients undergoing 4 common surgical procedures in 23 hospitals to develop a risk model for CPSP; 2352 men underwent open hernia repair. Patients with pain were identified by telephone at 1 and 3 months and referred to the hospital 4 months after surgery for a physical examination to confirm CPSP. Three validated tools were used: the Brief Pain Inventory (BPI) for severity, analgesic use, and interference with activities; the SF-12 questionnaire for QoL (validated Spanish version), and the Douleur Neuropathique 4 (DN4). Patients with CPSP were called again at 1 and 2 years. RESULTS: In 1761 patients who underwent hernia repair and were eligible for physical examination for CPSP, the incidence of confirmed pain at 4 months was 13.6% (patient-reported pain, 6.2% at 1 year and 4.0% at 2 years). Neuropathic pain was diagnosed in 38.5% of the CPSP patients at 4 months. The incidences of neuropathic CPSP in patients with mesh or non-mesh repairs were similar (38.6 and 33.3%, respectively). SF-12 physical component scores changed little in all patients, whether or not they developed CPSP. The SF-12 mental component decreased significantly in all patients, but the decrease was clinically significant only in CPSP patients. CPSP interfered with activities (18%), work (15.6%), walking (15%) and mood (10.2%). At 2 years 52.1% of CPSP patients had moderate/intense pain and 28.2% took analgesics. CONCLUSION: CPSP affects QoL-related activities, and although it diminishes over the course of 2 years after surgery, many patients continue to have moderate/intense pain and take analgesics. CPSP and neuropathic pain rates seem to be similar after mesh and non-mesh repair. BPI and SF-12 mental component scores detect effects on QoL. TRIAL REGISTRATION: ClinicalTrials.gov NCT01510496.

Olfactory threshold selectively predicts positive psychometric schizotypy.

Olfactory impairment might be useful as a non-invasive pre-morbid biological marker of psychosis. People with schizophrenia show consistent impairments, but an association between olfaction and schizotypy in non-clinical populations is inconclusive and has been somewhat controversial. This is important as impairment in patients may be artefacts of antipsychotic medication. Meta-analyses indicate small effect sizes in non-clinical populations, suggesting prior negative studies may have been underpowered to demonstrate them. We measured olfaction and psychometrically-defined schizotypy in a sample of 739 non-clinical volunteers [mean age 23.1]. Subsets reported whether they had a history of mental illness in the family or smoked. We used (sniffin' sticks) to measure threshold detection, discrimination and identification of odours. O-LIFE was used to measure schizotypy. Lower olfactory-threshold selectively predicted higher scores on the positive dimension, unusual experiences. This association was most evident in sub-groups reporting history of mental illness in the family and/or smoking. There was a weak trend for an association between identification and introvertive anhedonia and discrimination and cognitive disorganisation in those with a history of mental illness in the family. These data support the idea that olfaction merits further investigation as a biomarker for psychosis and that olfactory-threshold detection in particular has potential to selectively predict unusual experiences. Variability in previous studies may have been exacerbated by including different proportions of participants with history of mental illness in the family and/or smoking. We propose that non-clinical participants be stratified by these factors in future studies of olfaction and potentially any study that measures psychometric schizotypy.

Psychiatric framing affects positive but not negative schizotypy scores in psychology and medical students.

When testing risk for psychosis, we regularly rely on self-report questionnaires. Yet, the more that people know about this condition, the more they might respond defensively, in particular with regard to the more salient positive symptom dimension. In two studies, we investigated whether framing provided by questionnaire instructions might modulate responses on self-reported positive and negative schizotypy. The O-LIFE (UK study) or SPQ (New Zealand study) questionnaire was framed in either a "psychiatric", "creativity", or "personality" (NZ only) context. We tested psychology students (without taught knowledge about psychosis) and medical students (with taught knowledge about psychosis; UK only). We observed framing effects in psychology students in both studies: positive schizotypy scores were lower after the psychiatric compared to the creativity instruction. However, schizotypy scores did not differ between the creativity and personality framing conditions, suggesting that the low scores with psychiatric framing reflect defensive responding. The same framing effect was also observed in medical students, despite their lower positive schizotypy scores overall. Negative schizotypy scores were not affected by framing in either study. These results highlight the need to reduce response biases when studying schizotypy, because these might blur schizotypy-behaviour relationships.

Odd and disorganized-Comparing the factor structure of the three major schizotypy inventories.

Schizotypy is a personality-framework currently considered a comprehensive and useful construct in schizophrenia research and becoming ever more accepted within psychiatry. Thus, it is crucial to obtain a unifying and generally accepted means of its measuring. The three most commonly used psychometric schizotypy inventories, the Wisconsin Schizotypy Scales, Schizotypal Personality Questionnaire and Oxford-Liverpool Inventory of Feelings and Experiences were, however, built upon different theoretical schizotypy models, wherefore comparing results from studies that have used different inventories is difficult and sometimes questionable. Therefore, an analysis of all three inventories was conducted within the same sample of 327 healthy participants to illustrate the similarities and differences in factor structures. Results showed that findings are likely dependent on the used assessment instrument. A following item-level factor analysis was conducted to investigate the shared structure of all three inventories, in order to illustrate a framework interpretable as "common ground" between measures. This adjusted four-factor structure may be used to better aid comparisons between schizotypy-studies having used different inventories. At least, our findings illustrate the necessity of viewing individual results before the background of the theoretical framework of the respective measurement tool.

Psychotropic drugs and personality changes: A case of lithium.

BACKGROUND: The effect of psychopharmacological treatment on personality has been mostly studied with antidepressant drugs. Previously, we demonstrated an association between long-term lithium response and affective temperaments measured by the Temperament Scale of Memphis, Pisa, Paris and San Diego-Autoquestionnaire (TEMPS-A), and schizotypic traits, measured by the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE). Therefore, we were interested whether long-term lithium treatment per se may influence personality traits measured by these scales. METHODS: The study was performed on 40 patients with bipolar mood disorder (16 male, 24 female) with a mean age of 46 ± 10 years, either hospitalized or attending the outpatient clinic, Department of Adult Psychiatry, Poznan University of Medical Sciences. Among them, twenty patients (8 male, 12 female) have received lithium for 10-33 years, and twenty (8 male, 12 female) have never been exposed to lithium and have been given other mood-stabilizing drugs. Each patient, had the assessment made by the TEMPS-A and O-LIFE, during euthymic state. RESULTS: Patients on long-term lithium treatment were significantly older and had longer duration of bipolar illness compared with non-lithium patients. Lithium-treated patients obtained significantly lower scores of cyclothymic and irritable temperaments on the TEMPS-A, and of unusual experiences, cognitive disorganization and impulsive nonconformity on the O-LIFE. CONCLUSIONS: It is hypothesized that the differences in personality, revealed by the TEMPS-A and O-LIFE scales, are related to the long-term treatment with lithium. The decrease in cyclothymic temperament and in cognitive disorganization trait were previously shown to be associated with the therapeutic effect of lithium.

An electrophysiological insight into visual attention mechanisms underlying schizotypy.

A theoretical framework has been put forward to understand attention deficits in schizophrenia (Luck SJ & Gold JM. Biological Psychiatry. 2008; 64:34-39). We adopted this framework to evaluate any deficits in attentional processes in schizotypy. Sixteen low schizotypal (LoS) and 16 high schizotypal (HiS) individuals performed a novel paradigm combining a match-to-sample task, with inhibition of return (using spatially uninformative cues) and memory-guided efficient visual-search within one trial sequence. Behavioural measures and event-related potentials (ERPs) were recorded. Behaviourally, HiS individuals exhibited a spatial cueing effect while LoS individuals showed the more typical inhibition of return effect. These results suggest HiS individuals have a relative deficit in rule selection - the endogenous control process involved in disengaging attention from the uninformative location cue. ERP results showed that the late-phase of N2pc evoked by the target stimulus had greater peak latency and amplitude in HiS individuals. This suggests a relative deficit in the implementation of selection - the process of focusing attention onto target features that enhances relevant/suppresses irrelevant inputs. This is a different conclusion than when the same theoretical framework has been applied to schizophrenia, which argues little or no deficit in implementation of selection amongst patients. Also, HiS individuals exhibited earlier onset and greater amplitude of the mismatch-triggered negativity component. In summary, our results indicate deficits of both control and implementation of selection in HiS individuals.

Neural correlates of creative thinking and schizotypy.

Empirical studies indicate a link between creativity and schizotypal personality traits, where individuals who score highly on schizotypy measures also display greater levels of creative behaviour. However, the exact nature of this relationship is not yet clear, with only a few studies examining this association using neuroimaging methods. In the present study, the neural substrates of creative thinking were assessed with a drawing task paradigm in healthy individuals using fMRI. These regions were then statistically correlated with the participants' level of schizotypy as measured by the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE), which is a questionnaire consisting of four dimensions. Neural activations associated with the creativity task were observed in bilateral inferior temporal gyri, left insula, left parietal lobule, right angular gyrus, as well as regions in the prefrontal cortex. This widespread pattern of activation suggests that creative thinking utilises multiple neurocognitive networks, with creative production being the result of collaboration between these regions. Furthermore, the correlational analyses found the Unusual Experiences factor of the O-LIFE to be the most common dimension associated with these areas, followed by the Impulsive Nonconformity dimension. These correlations were negative, indicating that individuals who scored the highest in these factors displayed the least amount of activation when performing the creative task. This is in line with the idea that 'less is more' for creativity, where the deactivation of specific cortical areas may facilitate creativity. Thus, these findings contribute to the evidence of a common neural basis between creativity and schizotypy.

Dopaminergic foundations of schizotypy as measured by the German version of the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE)-a suitable endophenotype of schizophrenia.

The concept of schizotypy or "psychosis proneness" captures individual differences in perceptual, cognitive, and affective experiences that may relate to a range of psychotic disorders. The concept is an important way to assess the contribution of pre-existing psychological and genetically based biological features to the development of illnesses such as schizophrenia (so called endophenotypes). The Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE) is a widely used multi-dimensional measure of the construct and consists of four scales which mirror several groups of psychotic symptoms: Unusual Experiences (UnEx; positive symptoms), Cognitive Disorganization (CogDis; cognitive symptoms), Introvertive Anhedonia (IntAn; negative symptoms), and Impulsive Nonconformity (ImpNon; impulsive and antisocial symptoms). For the purpose of evaluating the suitability of schizotypy as an endophenotype of schizophrenia the current version of the O-LIFE was translated into German: its psychometric properties (including re-test reliability and construct validity) were examined in a large sample (n > 1200) and compared to those of the English original. The German version was both highly reliable and consistent with the original. The study aimed to show that schizotypy as measured by the O-LIFE can indeed be regarded as an endophenotype of schizophrenia in terms of genetic associations regarding relevant dopamine-related candidate polymorphisms of schizotypy [i.e., Val(158)Met-polymorphism of the COMT gene, uVNTR of the MAOA gene, Taq1A-polymorphism of the DRD2 gene, VNTR of the SLC6A3 (DAT) gene]. We also wanted to compare the genetic associations of the O-LIFE to those published using other operationalizations of schizotypy. Our results show a large number of significant associations and borderline-significant trends between the O-LIFE sub-scales and a range of genes, thereby supporting using the O-LIFE in the search for endophenotypic markers.